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Parental Educational Expectations,Academic Pressure,and Adolescent Mental Health:An Empirical Study Based on CEPS Survey Data 被引量:1
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作者 Tao Xu Fangqiang Zuo Kai Zheng 《International Journal of Mental Health Promotion》 2024年第2期93-103,共11页
Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating variable.Methods:This study was based ... Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating variable.Methods:This study was based on the baseline data of the China Education Panel Survey,which was collected within one school year during 2013–2014.It included 19,958 samples from seventh and ninth graders,who ranged from 11 to 18 years old.After removing missing values and conducting relevant data processing,the effective sample size for analysis was 16344.The OLS(Ordinary Least Squares)multiple linear regression analysis was used to examine the relationship between parental educational expectations,academic pressure,and adolescents’mental health problems.In addition,we established an interaction term between parents’educational expectations and academic pressure to investigate the moderating effect of academic stress.Results:The study found that adolescents whose parents had high educational expectations reported less mental health problems.(β=−0.195;p<0.001).Additionally,adolescents who had high academic pressure reported more mental health problems.(β=0.649;p<0.001).Furthermore,the study found that academic pressure had a significant moderating effect on the relationship between parental educational expectations and adolescents’mental health problems(β=0.082;p<0.001).Conclusion:Parental educational expectations had a close relationship with adolescents’mental health problems,and academic pressure moderated this relationship.For those adolescents with high levels of academic pressure,the association between high parental educational expectations and mental health problems became stronger.On the contrary,for those adolescents with low levels of academic pressure,the association between high parental educational expectations and mental health problems became weaker.These findings shed new light on how parental educational expectations affected adolescent mental health problems and had significant implications for their healthy development. 展开更多
关键词 Parental educational expectations academic pressure adolescent mental health problems
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Impact of cancer diagnosis on life expectancy by area-level socioeconomic groups in New South Wales, Australia: a population-based study
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作者 Md Mijanur Rahman Michael David +5 位作者 David Goldsbury Karen Canfell Kou Kou Paramita Dasgupta Peter Baade Xue Qin Yu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第8期692-702,共11页
Objective: Improvement in cancer survival over recent decades has not been accompanied by a narrowing of socioeconomic disparities. This study aimed to quantify the loss of life expectancy(LOLE) resulting from a cance... Objective: Improvement in cancer survival over recent decades has not been accompanied by a narrowing of socioeconomic disparities. This study aimed to quantify the loss of life expectancy(LOLE) resulting from a cancer diagnosis and examine disparities in LOLE based on area-level socioeconomic status(SES).Methods: Data were collected for all people between 50 and 89 years of age who were diagnosed with cancer, registered in the NSW Cancer Registry between 2001 and 2019, and underwent mortality follow-up evaluations until December 2020. Flexible parametric survival models were fitted to estimate the LOLE by gender and area-level SES for 12 common cancers.Results: Of 422,680 people with cancer, 24% and 18% lived in the most and least disadvantaged areas, respectively. Patients from the most disadvantaged areas had a significantly greater average LOLE than patients from the least disadvantaged areas for cancers with high survival rates, including prostate [2.9 years(95% CI: 2.5±3.2 years) vs. 1.6 years(95% CI: 1.3±1.9 years)] and breast cancer [1.6 years(95% CI: 1.4±1.8 years) vs. 1.2 years(95% CI: 1.0±1.4 years)]. The highest average LOLE occurred in males residing in the most disadvantaged areas with pancreatic [16.5 years(95% CI: 16.1±16.8 years) vs. 16.2 years(95% CI: 15.7±16.7 years)] and liver cancer [15.5 years(95% CI: 15.0±16.0 years) vs. 14.7 years(95% CI: 14.0±15.5 years)]. Females residing in the least disadvantaged areas with thyroid cancer [0.9 years(95% CI: 0.4±1.4 years) vs. 0.6 years(95% CI: 0.2±1.0 years)] or melanoma [0.9 years(95% CI: 0.8±1.1 years) vs. 0.7 years(95% CI: 0.5±0.8 years)] had the lowest average LOLE.Conclusions: Patients from the most disadvantaged areas had the highest LOLE with SES-based differences greatest for patients diagnosed with cancer at an early stage or cancers with higher survival rates, suggesting the need to prioritise early detection and reduce treatment-related barriers and survivorship challenges to improve life expectancy. 展开更多
关键词 Cancer diagnosis life expectancy loss of life expectancy area-level socioeconomic status flexible parametric model
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Transforming education:Developing a practice-ready workforce
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作者 Gwen Sherwood 《International Journal of Nursing Sciences》 CSCD 2024年第2期159-161,共3页
The well-known question,why do people keep doing the same thing but expect a different result,applies to nursing education.Healthcare delivery systems are in constant evolution yet much of nursing education operates w... The well-known question,why do people keep doing the same thing but expect a different result,applies to nursing education.Healthcare delivery systems are in constant evolution yet much of nursing education operates with traditional teaching approaches expecting to produce graduates suitable for rapidly changing healthcare delivery systems.Nursing is a practice-based discipline with its own body of knowledge situated within the context of dy-namic nursing practice.It is the responsibility of nursing academia to prepare graduates suitable for practice.If we are to change prac-tice,we must rethink education.The impact and interruptions of the global COVID-19 pandemic gave rise to questions on best prac-tices to guide nursing education into the future. 展开更多
关键词 EDUCATION situated EXPECT
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Kinematic calibration under the expectation maximization framework for exoskeletal inertial motion capture system
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作者 QIN Weiwei GUO Wenxin +2 位作者 HU Chen LIU Gang SONG Tainian 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期769-779,共11页
This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters ... This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters are calibrated by the traditional calibration method at first. Then, in order to calibrate the parameters affected by the random colored noise, the expectation maximization (EM) algorithm is introduced. Through the use of geometric parameters calibrated by the traditional calibration method, the iterations under the EM framework are decreased and the efficiency of the proposed method on embedded system is improved. The performance of the proposed kinematic calibration method is compared to the traditional calibration method. Furthermore, the feasibility of the proposed method is verified on the EI-MoCap system. The simulation and experiment demonstrate that the motion capture precision is significantly improved by 16.79%and 7.16%respectively in comparison to the traditional calibration method. 展开更多
关键词 human motion capture kinematic calibration EXOSKELETON gyroscopic drift expectation maximization(EM)
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Novel method for extraction of ship target with overlaps in SAR image via EM algorithm
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作者 CAO Rui WANG Yong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期874-887,共14页
The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition... The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be influenced.For addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is pro-posed.First,the scatterers of ship targets are obtained via the target detection technique.Then,the EM algorithm is applied to extract the scatterers of a single ship target with a single IPP.Afterwards,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be generated.The proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most possibly.Results of simulated and real mea-sured data demonstrate the effectiveness of the proposed method. 展开更多
关键词 expectation maximization(EM)algorithm image processing imaging projection plane(IPP) overlapping ship tar-get synthetic aperture radar(SAR)
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Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search
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作者 Xiao Liu Pingting Lin +2 位作者 Fan Bu Shaoling Zhuang Shoudao Huang 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期32-42,共11页
The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regressi... The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems. 展开更多
关键词 Generator optimization Gaussian Process Regression(GPR) Conditional Likelihood Lower Bound Search(CLLBS) Constraint improvement expectation(CEI) Finite element calculation
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Exploring the Interplay between Job Stress,Work Performance,and Attitudes toward Professional Psychological Help among Employees
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作者 Cong Minh Le Son Van Huynh +3 位作者 Ky Luu Quynh-Nhi Ngoc Ho Van Thi Le Nguyen Vinh-Long Tran-Chi 《International Journal of Mental Health Promotion》 2024年第7期531-545,共15页
Objective:This study explores the interplay between job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese employees.Methods:A total of 374 employ... Objective:This study explores the interplay between job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese employees.Methods:A total of 374 employees in Vietnam were surveyed using random sampling and an online questionnaire from November 07 to November 28,2023.Demographic data and self-reported from three scales:The New Job Stress Scale(NJSS),Work Performance(WP),and Attitudes Toward Seeking Professional Psychological Help(ATSPPH_SF)were collected.Results:Significant variations were found across several variables,including forms of work,operating hours,education levels,monthly income,numbers of daily working hours,and the presence of a psychological counseling department within the company.Our analysis has highlighted direct relationships between key latent variables.Employees who were more open to seeking professional help tended to report higher levels of job stress.The negative relationship was found between job stress and attitudes toward seeking professional help.Additionally,work effort was positively associated with work quality.Moderation analyses revealed the influence of co-worker support on role expectation conflict and work effort,role expectation conflict and work-life balance,as well as interactions between role expectation conflict and attitudes needed toward seeking professional help.Mediation analyses showed that work effort mediated relationships between openness to seeking professional help,co-worker support,work-life balance,role expectation conflict,and work quality.Attitudes toward seeking professional help also mediated relationships between work-life balance,job stress,and work quality.Conclusion:The study highlights the complex dynamics surrounding job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese employees.It highlights the importance of addressing help-seeking barriers,promoting work engagement,and fostering healthy work-life balance for employee well-being and productivity.Further research across diverse contexts and interventions is needed. 展开更多
关键词 Stress co-worker support work-life balance role expectation conflict professional psychological help-seeking
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Understanding factors affecting non-participants’interest in community-supported agriculture
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作者 Maula Fadhilata RAHMATIKA Agus SUMAN +1 位作者 Wildan SYAFITRI Sri MULJANINGSIH 《Regional Sustainability》 2024年第3期69-80,共12页
Community-supported agriculture(CSA)has emerged as a viable solution for addressing the agricultural challenges faced by countries like Indonesia.This study uses the wellestablished unified theory of acceptance and us... Community-supported agriculture(CSA)has emerged as a viable solution for addressing the agricultural challenges faced by countries like Indonesia.This study uses the wellestablished unified theory of acceptance and use of technology(UTAUT2)model to examine the interest in CSA of potential customers in Indonesia.A standardized questionnaire was distributed to 1200 respondents,and the data were analyzed using structural equation model-partial least square(SEM-PLS)in SmartPLS 4.0 software.The results capture potential CSA consumer interest and will help to improve CSA development strategies in Indonesia.The model explains 44.4%of customers’intentions,and identifies performance expectancy as the decisive factor in customers’willingness to participate in CSA.Performance expectancy(0.292),hedonic motivation(0.262),social influence(0.259),and facilitating conditions(0.086)positively influence customers’interest in participating in a CSA program.The adoption of CSA programs by both farmers and customers could be increased by implementing regulations that provide tax incentives and subsidies,offering training on sustainable farming practices,facilitating the establishment of distribution channels,and establishing guidelines for fair price and quality standards.This study shows the high potential for the implementation of CSA in Indonesia.It could also be used as a foundation for the development of new policies regarding sustainable agriculture markets in Indonesia. 展开更多
关键词 Community-supported agriculture(CSA) Sustainable agriculture Behavioral intention Performance expectancy Unified theory of acceptance and use of technology model Indonesia
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Lottery Numbers and Ordered Statistics
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作者 Kung-Kuen Tse 《Applied Mathematics》 2024年第4期287-291,共5页
The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typica... The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typically random and unpredictable. Some people use the lottery terminal randomly generates numbers for them, some players choose numbers that hold personal significance to them, such as birthdays, anniversaries, or other important dates, some enthusiasts have turned to statistical analysis as a means to analyze past winning numbers identify patterns or frequencies. In this paper, we use order statistics to estimate the probability of specific order of numbers or number combinations being drawn in future drawings. 展开更多
关键词 LOTTERY Order Statistics Hypergeometric Distribution EXPECTATION UNIFORM
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Exact controllability of rational expectations model with multiplicative noise and input delay
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作者 Wenjing Wang Juanjuan Xu +1 位作者 Huanshui Zhang Minyue Fu 《Journal of Automation and Intelligence》 2024年第1期19-25,共7页
This paper considers the rational expectations model with multiplicative noise and input delay,where the system dynamics rely on the conditional expectations of future states.The main contribution is to obtain a suffi... This paper considers the rational expectations model with multiplicative noise and input delay,where the system dynamics rely on the conditional expectations of future states.The main contribution is to obtain a sufficient condition for the exact controllability of the rational expectations model.In particular,we derive a sufficient Gramian matrix condition and a rank condition for the delay-free case.The key is the solvability of the backward stochastic difference equations with input delay which is derived from the forward and backward stochastic system. 展开更多
关键词 Rational expectations model Exact controllability Exactly null controllability Multiplicative noise Input delay
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Managing Homework-Related Stress:Strategies for Balancing Academic Demands and Mental Well-Being in Students
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作者 Xiyan Xenia Luo 《Cultural and Religious Studies》 2024年第8期556-558,共3页
This paper examines the growing issue of homework-related stress among students,focusing on the impact of academic demands,parental expectations,and social comparisons on students’mental health.While homework serves ... This paper examines the growing issue of homework-related stress among students,focusing on the impact of academic demands,parental expectations,and social comparisons on students’mental health.While homework serves as an important educational tool,its excessive volume and pressure can lead to psychological issues such as anxiety,depression,and burnout.Parental involvement,although beneficial,can heighten stress when coupled with unrealistic expectations.Additionally,social media exacerbates these pressures by promoting comparisons and idealized standards.The paper proposes a holistic approach,involving educators,parents,and students,to mitigate these stressors.Key strategies include assigning meaningful homework,fostering open communication,teaching time management skills,and encouraging a balance between academic success and mental well-being.By addressing homework-related stress,students can be supported in achieving both academic and personal success while maintaining their mental health. 展开更多
关键词 homework stress academic pressure mental health parental expectation social media comparison
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Modeling Expected Failure Considering Repair Time and Degradation: A Rail System Case Study
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作者 Maryam Hamidi Atefe Sedaghat +1 位作者 Amir Gharehgozli Ferenc Szidarovszky 《Journal of Transportation Technologies》 2024年第2期236-254,共19页
The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the i... The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the idea of expectation by conditioning, special Volterra-type integral equations are derived for general types of repairs, considering the length of repair and reduced degradation of the idle object. In addition to minimal repair and failure replacement, partial repairs are also discussed when the repair results in reduction of the number of future failures or decreases the effective age of the object. Numerical integration-based algorithm and simulation study are performed to solve the resulting integral equation. Since the geometry degradation in different dimensions of a rail track and controlling and maintaining defects are of importance, a numerical example using the rail industry data is conducted. Expected number of failures of different failure type modes in rail track is calculated within a two-year interval. Results show that within a two-year period, anticipated occurrences of cross level failures, surface failures, and DPI failures are 2.4, 3.8, and 5.8, respectively. 展开更多
关键词 Renewal Theory Expected Number of Failures Partial Repair Minimal Repair
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Management Practices:Shaping Employee Satisfaction and Commitment in Large German Companies
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作者 Lana Sosnovika 《Management Studies》 2024年第3期188-196,共9页
The rapid evolution of the political,economic,and social landscape has generated increased interest in understanding the contextual application of management styles and behaviours toward employees.In this context,orga... The rapid evolution of the political,economic,and social landscape has generated increased interest in understanding the contextual application of management styles and behaviours toward employees.In this context,organizations must comprehend and assess employee satisfaction to enhance productivity and realize their strategic and economic goals.Therefore,this study aims to investigate the prevailing and significant management behaviours toward employees in large German companies and their impact on employee satisfaction and job commitment.To achieve the research objective,the study will employ a qualitative method to explore management behaviours toward employees.Data were collected through interviews with randomly selected managers from different companies and departments.The study aims to uncover discrepancies or variations in employee expectations regarding management behaviour.The findings will provide a better understanding of the most prevalent and significant management behaviours toward employees in large German companies and their impact on employee satisfaction and job commitment.The results will be valuable to management in adopting suitable leadership styles and improving employee satisfaction,leading to increased productivity and organizational performance.The research will contribute to the existing body of knowledge in the field of management and human resource management by providing insights into the impact of management behaviours on employees.It will also offer recommendations to management on how to enhance employee satisfaction and job commitment,leading to improved organizational performance.In conclusion,this study will investigate the prevailing management behaviours toward employees in large German companies and their impact on employee satisfaction and job commitment. 展开更多
关键词 employee commitment employee expectations employee satisfaction management practices in large German companies leadership approaches organizational performance
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Research Progress and Prospects of Magnetic Nanomaterials
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作者 Jia Xu Jingming Li Jun Shi 《Expert Review of Chinese Chemical》 2024年第1期5-8,共4页
Nanomaterials are one of the research and development hotspots in the field of cutting-edge new materials,and also an important strategic emerging industry.Magnetic nanomaterials have broad application prospects in fi... Nanomaterials are one of the research and development hotspots in the field of cutting-edge new materials,and also an important strategic emerging industry.Magnetic nanomaterials have broad application prospects in fields such as chemical engineering,new materials,electronic information,and biomedicine.This article introduces the application progress and preparation methods of magnetic nanomaterials,and puts forward suggestions for further optimizing the preparation process of magnetic nanomaterials and developing new magnetic materials with better performance. 展开更多
关键词 MAGNETISM NANO MATERIALS application PREPARATION EXPECTATION
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基于Expect的自动化运维分析与设计
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作者 姜家文 潘祺喆 陈彦锋 《现代计算机》 2024年第13期82-85,共4页
信息安全问题层出不穷,设备国产化要求也越来越高。终端信息统计、软件安装与运行、设备远程开关机等批量终端管理,逐步成为常态化工作。维护模式固定、操作简单,但是终端数量较多的情况下,费时费力且容易出错。以国产麒麟操作系统为例... 信息安全问题层出不穷,设备国产化要求也越来越高。终端信息统计、软件安装与运行、设备远程开关机等批量终端管理,逐步成为常态化工作。维护模式固定、操作简单,但是终端数量较多的情况下,费时费力且容易出错。以国产麒麟操作系统为例,设计了基于Expect的批量终端自动化巡检脚本,展示了终端ip地址、MAC地址、磁盘序列号等自动获取方法,远程终端软件安装与运行,回传合并统计数据等功能,给Linux终端运维人员提供一个新的运维思路。 展开更多
关键词 EXPECT 自动化 运维 信息统计
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Exceeding Expectations
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《ChinAfrica》 2024年第2期16-17,共2页
The Chinese economy continued to rebound and made solid progress in 2023,despite the complex international situation and numerous risks and challenges.The accelerated economic structural transformation and upgrade,cou... The Chinese economy continued to rebound and made solid progress in 2023,despite the complex international situation and numerous risks and challenges.The accelerated economic structural transformation and upgrade,coupled with increasing economic resilience,has resulted in various highlights. 展开更多
关键词 EXPECTATION continued ECONOMIC
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Keeping Commitments,Meeting Expectations
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作者 HANNAH WANJIE RYDER CHEN HUIYI 《ChinAfrica》 2024年第9期38-40,共3页
How well is FOCAC meeting Africa’s aspirations for development?The idea of establishing the Forum on China-Africa Cooperation(FOCAC)in 2000 initially came from African countries,eager to coordinate and manage their r... How well is FOCAC meeting Africa’s aspirations for development?The idea of establishing the Forum on China-Africa Cooperation(FOCAC)in 2000 initially came from African countries,eager to coordinate and manage their relationship with China. 展开更多
关键词 China. EXPECTATION establishing
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Research on the Construction and Application of Service Quality Evaluation Models for Scenic Spots:Taking Chongqing Ciqikou as an Example
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作者 Ziyan Zhao Yanling Jiang 《Proceedings of Business and Economic Studies》 2024年第4期73-79,共7页
In the current environment of increasingly fierce competition in the tourism industry,service quality has become crucial for enhancing the competitiveness of scenic spots.This paper uses the SERVQUAL model to design a... In the current environment of increasingly fierce competition in the tourism industry,service quality has become crucial for enhancing the competitiveness of scenic spots.This paper uses the SERVQUAL model to design a service quality evaluation questionnaire that captures the gap between tourists’expectations and perceptions,using the Ciqikou Scenic Spot as a case study.Data collected from field surveys are used to comprehensively and meticulously evaluate the service quality of the Ciqikou Scenic Spot.The analysis results show that the scenic spot,with its unique folk culture experience and beautiful ecological environment,has certain advantages in terms of service quality.However,significant deficiencies exist in infrastructure and environmental hygiene.Accordingly,targeted improvement suggestions are proposed to further enhance the service quality of the Ciqikou Scenic Spot and meet the increasingly diverse and personalized needs of tourists.This study provides not only a specific service quality improvement strategy for the Ciqikou Scenic Spot but also a valuable reference for other tourist attractions. 展开更多
关键词 Service quality SERVQUAL model Tourists’perception Tourists’expectation CIQIKOU
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A Novel Adaptive Kalman Filter Based on Credibility Measure 被引量:3
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作者 Quanbo Ge Xiaoming Hu +2 位作者 Yunyu Li Hongli He Zihao Song 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第1期103-120,共18页
It is quite often that the theoretic model used in the Kalman filtering may not be sufficiently accurate for practical applications,due to the fact that the covariances of noises are not exactly known.Our previous wor... It is quite often that the theoretic model used in the Kalman filtering may not be sufficiently accurate for practical applications,due to the fact that the covariances of noises are not exactly known.Our previous work reveals that in such scenario the filter calculated mean square errors(FMSE)and the true mean square errors(TMSE)become inconsistent,while FMSE and TMSE are consistent in the Kalman filter with accurate models.This can lead to low credibility of state estimation regardless of using Kalman filters or adaptive Kalman filters.Obviously,it is important to study the inconsistency issue since it is vital to understand the quantitative influence induced by the inaccurate models.Aiming at this,the concept of credibility is adopted to discuss the inconsistency problem in this paper.In order to formulate the degree of the credibility,a trust factor is constructed based on the FMSE and the TMSE.However,the trust factor can not be directly computed since the TMSE cannot be found for practical applications.Based on the definition of trust factor,the estimation of the trust factor is successfully modified to online estimation of the TMSE.More importantly,a necessary and sufficient condition is found,which turns out to be the basis for better design of Kalman filters with high performance.Accordingly,beyond trust factor estimation with Sage-Husa technique(TFE-SHT),three novel trust factor estimation methods,which are directly numerical solving method(TFE-DNS),the particle swarm optimization method(PSO)and expectation maximization-particle swarm optimization method(EM-PSO)are proposed.The analysis and simulation results both show that the proposed TFE-DNS is better than the TFE-SHT for the case of single unknown noise covariance.Meanwhile,the proposed EMPSO performs completely better than the EM and PSO on the estimation of the credibility degree and state when both noise covariances should be estimated online. 展开更多
关键词 CREDIBILITY expectation maximization-particle swarm optimization method(EM-PSO) filter calculated mean square errors(MSE) inaccurate models Kalman filter Sage-Husa true MSE(TMSE)
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Vector Approximate Message Passing with Sparse Bayesian Learning for Gaussian Mixture Prior 被引量:2
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作者 Chengyao Ruan Zaichen Zhang +3 位作者 Hao Jiang Jian Dang Liang Wu Hongming Zhang 《China Communications》 SCIE CSCD 2023年第5期57-69,共13页
Compressed sensing(CS)aims for seeking appropriate algorithms to recover a sparse vector from noisy linear observations.Currently,various Bayesian-based algorithms such as sparse Bayesian learning(SBL)and approximate ... Compressed sensing(CS)aims for seeking appropriate algorithms to recover a sparse vector from noisy linear observations.Currently,various Bayesian-based algorithms such as sparse Bayesian learning(SBL)and approximate message passing(AMP)based algorithms have been proposed.For SBL,it has accurate performance with robustness while its computational complexity is high due to matrix inversion.For AMP,its performance is guaranteed by the severe restriction of the measurement matrix,which limits its application in solving CS problem.To overcome the drawbacks of the above algorithms,in this paper,we present a low complexity algorithm for the single linear model that incorporates the vector AMP(VAMP)into the SBL structure with expectation maximization(EM).Specifically,we apply the variance auto-tuning into the VAMP to implement the E step in SBL,which decrease the iterations that require to converge compared with VAMP-EM algorithm when using a Gaussian mixture(GM)prior.Simulation results show that the proposed algorithm has better performance with high robustness under various cases of difficult measurement matrices. 展开更多
关键词 sparse Bayesian learning approximate message passing compressed sensing expectation propagation
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